Archived film analysis and restoration

The progressive degradation of current film archives poses a serious threat to the preservation of our cultural and technical heritage. Digitization and digital restoration are currently the most viable solutions for the long term preservation and high quality restoration of filmed material. They also open the path for more effective search, reuse and distribution of the archived content. This thesis covers various aspects of digital restoration applied to archived film. The main focus here lies on blotch restoration in conditions of difficult object motion. The topics covered in this thesis include: - Classification of complex events in degraded image sequences, in order to separate the temporally impulsive events into artefact areas and areas with difficult motion. - Spatial restoration of blotches (dirt, or gelatin loss), through virtual reconstruction of object edges followed by guided inpainting or constrained texture synthesis. - Spatiotemporal restoration of blotches by combining spatial edge-based restoration and temporal restoration techniques. - Restoration of the vinegar syndrome (combined with emulsion melting), a special type of artefact that represents one of the main problems of current film archives. - Object tracking, which can be used for enhancing the results of the motion estimation step that is performed in most temporal restoration algorithms. Extensive tests were performed, in order to validate the proposed algorithms and to show their readily application to real world cases.